Table 3 Characteristics of different risk groups
No risk factor (n=108) | One risk factor (n=66) | Two risk factors (n=26) | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Mean ± SD or n and (%) | 95% confidence interval | n* | Mean ± SD or n and (%) | 95% confidence interval | n* | p-value (0 vs. 1 RF) | Mean ± SD or n and (%) | 95% confidence interval | n* | p-value (0 vs. 2 RF) | p-value (1 vs. 2 RF) | |||||||
Characteristics | ||||||||||||||||||
Female sex, no [%] | 90 | 83.3% | 53 | 80.3% | 23 | 88.5% | ||||||||||||
Age [years] | 55.5 | ± | 12.1 | 53.2 to 57.9 | 59.4 | ± | 13.9 | 56.0 to 62.8 | 60.9 | ± | 13.5 | 55.5 to 66.4 | 0.002 | 0.20 | ||||
Height [cm] | 167.3 | ± | 8.3 | 165.7 to 168.9 | 166.2 | ± | 8.8 | 164.0 to 168.4 | 160.1 | ± | 7.7 | 157.8 to 164.0 | ||||||
Weight [kg] | 72.8 | ± | 15.4 | 69.8 to 75.7 | 70.6 | ± | 16.7 | 66.5 to 74.7 | 66.3 | ± | 15.9 | 59.8 to 72.7 | ||||||
Type of systemic sclerosis | ||||||||||||||||||
Limited cutaneous SSc [%] | 80 | 74.1% | 47 | 71.2% | 19 | 73.1% | ||||||||||||
Diffuse cutaneous SSc [%] | 27 | 25% | 17 | 25.8% | 7 | 26.9% | ||||||||||||
Early SSc [%] | 1 | 0.9% | 2 | 3% | 0 | |||||||||||||
Duration SSc [days] | 3398.6 | ± | 3432.2 | 2737.6 to 4059.6 | 106 | 2646.8 | ± | 2282.3 | 2081.3 to 3212.3 | 65 | 4829.9 | ± | 4089.4 | 3178.2 to 6481.7 | 0.011 | |||
WHO-FC, no [%] | Overall <0.0001 | |||||||||||||||||
I | 27 | 25% | 16 | 24.2% | 2 | 7.7% | ||||||||||||
II | 60 | 55.6% | 33 | 50.0% | 6 | 23.1% | ||||||||||||
III | 21 | 19.4% | 17 | 25.8% | 16 | 61.5% | ||||||||||||
IV | 0 | 0 | 2 | 7.7% | ||||||||||||||
Lung function | ||||||||||||||||||
Vital capacity max [l] | 3.1 | ± | 0.9 | 3.0 to 3.3 | 107 | 3.0 | ± | 1.0 | 2.8 to 3.3 | 64 | 2.3 | ± | 0.8 | <0.001 | 0.004 | |||
Forced expiratory volume in one second [l] | 2.5 | ± | 0.8 | 3.4 to 2.7 | 107 | 2.4 | ± | 0.8 | 2.2 to 2.6 | 65 | 1.9 | ± | 0.6 | 1.6 to 2.1 | 0.001 | 0.010 | ||
Total lung capacity [l] | 5.2 | ± | 1.2 | 5.0 to 5.5 | 107 | 5.1 | ± | 1.3 | 4.8 to 5.5 | 65 | 4.1 | ± | 1.2 | 3.6 to 4.5 | <0.001 | 0.001 | ||
Diffusion capacity of the lung for carbon monoxide SB [%] | 66.4 | ± | 16.4 | 63.3 to 69.5 | 49.8 | ± | 13.1 | 46.5 to 53.0 | <0.001 | 38.0 | ± | 13.2 | 32.4 to 43.6 | 24 | <0.001 | 0.004 | ||
Diffusion capacity of the lung for carbon monoxide/VA [%] | 83.8 | ± | 15.6 | 80.8 to 86.8 | 62.0 | ± | 13.6 | 58.6 to 65.3 | <0.001 | 48.0 | ± | 12.0 | 43.2 to 52.8 | <0.001 | <0.001 | |||
Laboratory | ||||||||||||||||||
N-terminal pro-brain natriuretic peptide [ng/l] | 222.7 | ± | 323.9 | 158.8 to 286.7 | 101 | 467.4 | ± | 910.0 | 223.7 to 711.1 | 56 | 908.3 | ± | 1291.9 | 335.5 to 1481.1 | 22 | <0.001 | 0.048 | |
C-reactive protein [mg/l] | 6.6 | ± | 10.0 | 4.7 to 8.5 | 107 | 5.2 | ± | 4.7 | 4.1 to 6.4 | 64 | 10.0 | ± | 9.6 | 6.1 to 13.8 | ||||
Glomerular filtration rate [ml/min/1.73m2] | 87.8 | ± | 24.4 | 83.0 to 92.5 | 103 | 87.1 | ± | 29.6 | 79.2 to 94.9 | 57 | 76.3 | ± | 25.1 | 65.1 to 87.4 | 22 | |||
Creatinine [mg/dl] | 0.78 | ± | 0.18 | 0.75 to 0.82 | 107 | 0.87 | ± | 0.55 | 0.73 to 1.0 | 64 | 1.33 | ± | 2.38 | 0.36 to 2.29 | 0.023 | |||
6-minute walking distance [meters] | 459.5 | ± | 82.4 | 443.3 to 475.7 | 102 | 438.1 | ± | 106.1 | 410.9 to 465.3 | 61 | 362.0 | ± | 104.0 | 318.1 to 405.9 | 24 | <0.001 | 0.003 | |
Echocardiography | ||||||||||||||||||
Right atrial area [cm2] | 11.7 | ± | 3.2 | 11.1 to 12.3 | 106 | 12.5 | ± | 4.3 | 11.5 to 13.6 | 65 | 14.5 | ± | 4.2 | 12.8 to 16.2 | 25 | |||
Right ventricular area [cm2] | 14.1 | ± | 3.4 | 13.5 to 14.8 | 107 | 15.1 | ± | 3.8 | 14.2 to 16.1 | 16.7 | ± | 3.7 | 15.2 to 18.2 | |||||
Systolic pulmonary arterial pressure [mmHg] | 26.3 | ± | 5.5 | 25.3 to 27.3 | 32.1 | ± | 12.2 | 29.1 to 35.1 | 0.001 | 55.4 | ± | 17.3 | 48.5 to 62.4 | <0.001 | <0.001 | |||
Tricuspid annular plane systolic excursion [mm] | 25.1 | ± | 4.2 | 24.3 to 25.9 | 23.9 | ± | 4.2 | 22.9 to 24.9 | 19.4 | ± | 3.9 | 17.8 to 20.9 | <0.001 | <0.001 | ||||
Right heart catheter | ||||||||||||||||||
Mean pulmonary arterial pressure [mmHg] | 17.3 | ± | 5.1 | 16.4 to 18.3 | 20.2 | ± | 6.8 | 18.5 to 21.9 | 0.019 | 34.9 | ± | 10.7 | 30.5 to 39.2 | <0.001 | <0.001 | |||
Cardiac output [l/min] | 5.6 | ± | 1.5 | 5.3 to 5.9 | 5.3 | ± | 1.3 | 5.0 to 5.7 | 5.1 | ± | 1.2 | 4.6 to 5.6 | ||||||
Pulmonary arterial wedge pressure [mmHg] | 9.1 | ± | 4.2 | 8.3 to 9.9 | 9.7 | ± | 4.0 | 8.7 to 10.7 | 10.7 | ± | 5.1 | 8.7 to 12.8 | ||||||
Pulmonary vascular resistance [WU] | 1.5 | ± | 0.6 | 1.4 to 1.7 | 2.2 | ± | 1.3 | 1.8 to 2.5 | 0.012 | 5.1 | ± | 2.9 | 3.9 to 6.3 | <0.001 | <0.001 | |||
Pulmonary arterial compliance [ml/mmHg] | 5.3 | ± | 2.3 | 4.8 to 5.7 | 100 | 4.0 | ± | 2.1 | 3.5 to 4.5 | 60 | 0.001 | 2.1 | ± | 1.0 | 1.7 to 2.6 | 22 | <0.001 | 0.001 |
RV pulmonary vascular reserve [mmHg/l/min] | 3.1 | ± | 2.0 | 2.8 to 3.5 | 107 | 6.1 | ± | 15.2 | 2.4 to 9.8 | 9.6 | ± | 7.6 | 6.5 to 12.6 | |||||
Cardiac index [l/min/m2] | 3.1 | ± | 0.8 | 3.0 to 3.3 | 3.1 | ± | 0.8 | 3.1 to 2.9 | 3.0 | ± | 0.5 | 2.8 to 3.2 | ||||||
Cardiac index increase during exercise [l/min/m2] | 3.3 | ± | 1.6 | 2.9 to 3.6 | 2.7 | ± | 1.5 | 2.4 to 3.1 | 1.5 | ± | 0.8 | 1.2 to 1.8 | ||||||
Peak cardiac index [l/min/m2] | 6.4 | ± | 1.7 | 6.1 to 6.7 | 5.8 | ± | 1.7 | 5.4 to 6.2 | 4.5 | ± | 1.0 | 4.1 to 4.9 | ||||||
Right ventricular pump function | Overall <0.0001 | |||||||||||||||||
Normal | 105 | 98.1% | 59 | 89.4% | 15 | 57.7% | ||||||||||||
Mild impairment | 0 | 5 | 7.6% | 4 | 15.4% | |||||||||||||
Moderate impairment | 0 | 0 | 4 | 15.4% | ||||||||||||||
Severe impairment | 2 | 1.9% | 2 | 3.0% | 3 | 11.5% | ||||||||||||